N-[(4-anilinoanilino)methyl]maleimide



United States Patent Filed May 17, 1962, Ser. No. 195,408

This invention relates to a new chemical compound, namely N-[(4-anilinoanilino)methyl]maleimide, and to the method of preparing same.

The subject compound, N-[(4-anilinoanilino)methyl] maleimide, is represented by the formula:

According to the invention, said compound can be prepared by reacting N-methylolmaleimide with N-phenyl-pphenylene diamine in an inert solvent. The reaction may be illustrated as follows:

H CH- The compound of this invention, N-[(4anilinoanilino) methylhnaieimide, may be used as an antioxidant in rubbers.

The following examples illustrate the invention:

Example I 25.4 grams of N-methylol maleimicle were dissolved in 200 ml. of dioxane and placed in a 500 ml. flask. To this solution were added 36.8 grams of N-phenyl-p-phenylene diamine and the mixture refluxed for one hour. The resultant solution was concentrated to one-half its volume and diluted with petroleum ether. An orange-yellow product, N-[(4-anilinoanilino)methyl]maleimide, was recrystallized from benzene and had a melting point of 125 -126 C.

Analysis for C H N O percent N calculated=14.34; percent N found=14.13.

Example 11 This example demonstrates the use of N-[(4-anilinoanilino)rnethyl]maleimide as an antioxidant in rubber stocks, particularly Hevea rubber stocks. Natural rubber (smoked sheet #2) was compounded conventionally with filler and pigment in standard sulfur-accelerator recipes containing 2.0 parts of N-[ (4-anilinoanilino)methyl]maleimide. By way of comparison, similar stocks were prepared by replacing this chemical, in one case, with a wellknown antioxidant combination such as BLE and JZF, and, in the other case, with no antioxidant. All the in gredients except the sulfur and accelerator were assembled and mixed in the Banbury. Discharge temperature was 275300 F. The sulfur and accelerator were added on a cool two-roll mill. All stocks were cured in a press 3,182,072 iatented May 4, 1965 ice at 293 F. and tested by the conventional testing methods used for rubber.

8 Reaction product of acetone and diphenylamine. (Marketed by Naugatuek Chem. Div., U.S. Rubber 00.)

b N,N-diphenyl-p-phenylenedlamine. (Marketed by Naugatuck Chem. Div., U.S. Rubber Co.)

The following table shows the results of tests made on the cured stocks before and after aging in air and in the presence of oxygen.

Physical Properties 1 2 3 Unaged: 30' 4, 350 3,920 4, 255 Tensile Strength (p.s.i.) 45 4,170 3, 900 4, 210 3, 865 3, 750 3, 875

30' 550 580 520 Elongation Break (percent) 45 540 600 530 90 560 610 510 30 775 750 850 Modulus 200% (p.s.i.)-.. 45' 725 625 800 90 625 540 725 Aged in Air-72 hrs. 212 F.: 30 l, 710 2,105 1, 330 Tensile Strength (p.s.i.) 45 1, 710 1, 780 1,155 90 1, 635 1, 585 1, 265

30 230 320 230 Elongation Break (percent) 45 220 290 230 90 250 290 270 30' l, 325 1, 1, 000 Modulus 200% (p.s.i 45 1,275 1, 015 950 90 1, 075 900 850 Aged-95 hrs. in Oxygen Bomb: 30 2, 900 2, 835 935 Tensile Strength (p.s.i.) 45 2, 315 2, 765 870 90 2, 315 2, 345 1, 630

30' 420 470 310 Elongation Break (percent) 45 370 450 300 90' 380 450 360 30 975 825 550 Modulus 200% (9.5.1.) 45 950 775 570 90 835 730 625 Aged-144 hrs. in Oxygen Bomb: 30 2, 275 2, 250 355 Tensile Strength (p.s.i.) 45' 2,010 1, 925 530 90 1, 835 1, 565 870 30 360 410 Elongation Break (pereent) 45 340 400 230 90 340 360 280 30' 925 815 300 Modulus 200% (p.s.i.)------ 45 890 775 315 90 780 650 376 Having thus described my invention, what I claim and desire to protect by Letters Patent is:

N- 4-anilino anilino) methyl] maleimide.

References Cited by the Examiner UNITED STATES PATENTS 1,915,334 6/33 Salzberg et al 260-243 2,425,320 8/47 Hill 252-149 2,710,872 6/55 Thompson 260-3265 2,726,249 12/55 Middleton 260-3265 2,743,260 4/56 Tawney 260326.5 2,998,468 8/61 Wilde et al. 260-800 3,024,217 3/62 Kibler 260-458 IRVING MARCUS, Primary Examiner.

NICHOLAS S. RIZZO, Examiner. 

